Lyman first entered his proposal in August 2012, but was disqualified because the machine exceeded the budget of $250. After modifying the project, he resubmitted it under the name “The Lyman Filament Extruder II”. This time the machine’s design met the budget restriction and was able to extrude different filament diameters, saving up to 80 percent on material costs. Both of Lyman’s open-source inventions have already been downloaded 12,000 times, enabling people to build their own filament extruding machines.

The machine works by filling a hopper with plastic pellets, which are then heated to their melting point. The resulting molten plastic is squeezed into filament and pushed through a nozzle onto the floor.

To highlight the cost benefits, for instance, if one wanted to make 392 chess pieces using a 3D printer, it would require the purchase of 2.2 pounds of plastic, which costs about $50. With the filament produced at home using Lyman’s machine, the price would drop to just $10. Buying the pellets in 55-pound bulks could cut the price even further to just $5.